In the packaging industry carton blank feeding systems generally involves moving a stack of vertically oriented carton blanks. Carton blank feeding devices used in known carton forming machines, in general are one of two types.
In the first type, the carton blank feeding device uses two parallel carton blank holding arms extended outwards from the entrance of the carton forming machine. The two carton blank holding arms are mounted at the front of the carton forming machines at 45° to vertical, and two pusher arms are connected with the two parallel carton blanks holding arms. At the lower end of each of the pusher arms, a heavy metal weight hangs. In use, a stack of vertically oriented folded carton blanks is placed in the parallel blank holding arms, the two sides of the carton blanks are held by the holding arms, and at the back of the carton blanks, the pusher arm is attached at the last carton blank. The gravity force and the 45° slant slide the carton blanks towards the carton forming device.
In the second type, the feeding device uses a set of two long carton blanks supporting arms, which are parallel to each other and mounted on the front end of the carton forming machine. In the middle of the bottom of the two long carton blanks supporting arms, two conveyor belts are mounted. A pusher arm is also mounted at one of the carton blanks supporting arms. In use, the carton blanks are placed in the space between the two long carton blanks supporting arms and the carton blanks are driven to the carton forming machine by the conveyor belts. The pusher arm with sensors will push the carton blanks towards the machine.
The problems of these two types of carton blank feeding systems are that, first of all, when the carton blanks are running out, a worker needs to stop the machine to refill the carton blanks into the feeding device. Frequently stopping the machine means waste of production time. Also, use of the gravity force and the 45° slant to slide the carton blanks can cause blanks to jam, especially when the number of carton blanks is low such that the carton blanks are not heavy enough to smoothly slide to the machine. Secondly, after a stack of vertically folded blanks is loaded, a manual adjustment/check must be done to ensure that the blanks are in the right position for the blanks to open. If the carton blanks are not in the right position, the machine will jam. This kind of adjustment is time consuming and decreases the productivity of the machine. Thirdly, another disadvantage of feeding stacks of vertically oriented carton blanks is that because the carton blanks stand in the feeder on the carton flaps, the quality of the carton and the weight of the blanks may cause the carton blanks to resist movement in the feeder and jam. Further, if a user wants to load more carton blanks into the feeder at one time to increase capacity between reloading, the carton blank feeder needs to be longer, which requires more floor space.
Accordingly, it would be desirable to provide a method to store and transport the folded carton blanks to the carton blanks opening device without stopping the machine, and/or to adjust the stack of folded blanks and/or to eliminate or reduce the need for further floor space in order to load larger volumes of carton blanks.